Process of producing a hard copper alloy.



. STATES PATENT "OFFICE.

OSCAR c. M. Knunsnn, or BROOKLYN, NEW YORK.

PROCESS OF PRODUCII IG A HARD COPPER ALLOY.

No Drawing.

To all whomc't may concern:

Be it known thatI, Oscar: G M; KNUD- SEN, a citizen of the UnitedStates, residing at Brooklyn, in the county of Kings and .State of NewYork,'have invented a new and useful Processof Producing a Hard Copper.Alloy,'of which the following is a speci- Thepresent invention relatesto a novel process of producing a hard copper alloy, saidalloyco'nsistingchiefly of copper and a relatively small percentage ofaluminum.

"A copper aluminum alloy per se is not new, and various methods ofuniting them have been employed "with some degree of success, but it hasbeen found that by first "cent. the hardness of tool steel, although thealloy, by changing the proportions of copper and aluminum used, can beof various v hardnesses, down to about-45 per cent. the

hardness of tool steel.- The product, although sufiiciently hard, whenformed into a lathe tool to cut steel and other hard met a-ls,,is not asbrittle and frangible as steel, and is not subject to rusting orcorrosion. It has ,lso been proven by'tests, that the productibf thepresent process possesses an appreciable degree of elasticityand'resiliency, in addition to its hardness, thus rendering the alloy ofadvantage for many uses. In

fact, the alloy can be used wherever a hard wear and corrosion-resistingmetal is desirable. For example, the alloy can be used forpropeller'shafts to withstand the great strains and conditions to whichthey are subjected, it not infrequently happening that steel propellershafts snap and break, 7

resultingin delays and expenses, as well as ossible danger to life. Thealloy can also he usedfor the construction of ship hulls to withstandthe strains and to prevent the rusting and corrosion of the hulls. Forthese and many other uses, the alloy will be Specification of LettersPatent. Patented May 28, 1918, Application filed March 22,1917. SerialNo. 156,744. i. a 3

particularly advantageous andsuperior to metalsnow used, even though thealloy may the degree of hardness desired,.the balance of the-alloy (from86 to 88 per cent.) being copper in its pure or commercial form. Thealuminum is melted in a crucible, and after being melted has addedthereto, the unmelted copper, which is broken up in small particles. Thetemperature is then increased to or slightly above the melting point ofcopper, and during the increase in temperature, the particles ofcopperare thoroughly mixed or'stirred with the molten aluminum, wherebyas the .temperature of the aluminum increases to the melting point ofcopper, the copper will be thoroughly admixed with the aluminum. It isthe addition of with the molten aluminumand-the mixing thereof together,which has been found to result in the superior hardening of the alloyswhen it cools. It has been foundthat;

the mixing, of the two molten metalsllto-j, gether, or the mixing ofaluminumflwith,

molten copper does not producetheresnlts obtained by the presentprocess. The.

molten alloy can be case, rolled, forged on otherwise worked while stillhot, and can:

be used for the production of knives, valves, shafts and various otherarticles of manu- "facture. v

Having thus described the invention, what is claimed as new is .Theprocess of producing a hard alloy composed chiefly of copper-and havingonly a small percentage of aluminum, consist ing in melting the aluminumfirst, then add-' ing thereto the copper broken up into small particles,then increasing the temperaturemy own, I have'hereto ailixed mysignature in the presence of two witnesses.

. OSCAR O.-'M. KNUDSEN.

; Witnesses: v

' IvY'E. Smrson,

Mormon E. Mum.

75 the particles of copper in unmelted state 1

